Planing type speed boat hull



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United States Patent 3,148,652 PLANING TYPE SPEED BOAT HULL Henry Donaldanazzi, 178 Sewett Parkway, Buffalo, NA. Filed Aug. 31, 1962, Ser. No.220,688 10 Claims. (Cl. 114-665) My invention relates to boat hulls andmore particularly to speed boat hulls of the type shown in my Patent2,900,- 945 and in my copending application Serial No. 43,944 now PatentNo. 3,051,115.

An object of the present invention is to provide this type of hull withbottom surfaces formed and arranged to cause the hull to bank toward theinside of a turn, thereby to improve its maneuverability, especially athigher speeds and thereby to reduce the tripping action and tendencysuch hulls have to overturn when tight turns are made at higher speeds.

Another object is to provide such a hull with bottom surfaces formed andarranged to cooperate during turns in generating a lift which cause itto readily bank to the inside of a turn, thereby reducing the normaltendency to trip and overturn on tight, highspeed turns.

Another object is to provide such a hull with an airdisplaced watertunnel having a central fore and aft tun nel-dividing member formed andarranged therein and extending from adjacent the bow rearwardly to thestern to divide the tunnel into spaced tunnel portions each serving todirect water passing therethrough away from the propeller of an outboardmotor securable to the stern in the usual manner, thereby to avoidproviding excessive cavitation in said water by the propeller.

FIGURE 1 is a side elevational view of a hull constructed in accordancewith the principles of my present invention.

FIGURE 2 is a bottom plan view of the hull shown in FIGURE 1.

FIGURE 3 is an enlarged rear elevational view of the hull shown inFIGURE 1.

FIGURE 4 is an enlarged transverse sectional view taken on the line 44of FIGURE 1.

FIGURE 5 is an enlarged transverse sectional view taken on the line 55of FIGURE 1, and

FIGURE 6 is a fragmentary detail horizontal sectional view taken on theline 66 of FIGURE 1.

Referring now to the drawings wherein like reference numerals denotelike parts in the several views, a hull constructed to attain theobjects of my present invention is generally indicated by the numeral10.

As in my copending application, Serial No. 43,944 (Patent No.3,051,115), the hull 10 of a generally rectangular shape is formed witha bottom surface 11 extending between its side walls 12 and its bow 13and stern 14 and is formed with a central fore and aft tunnel 15extending between the bow 13 and the stern 14. As in said copendingapplication, a spaced pair of bow stems 16 is provided, each beingspaced inwardly from one side 12 of the hull, and each bow stem isalined with the longitudinal center of one of a pair of spaced planingsurfaces 17 which are also spaced inwardly from the associated side wall12.

The fore half of the top wall or roof of the tunnel 15, as indicated bybroken lines in FIGURE 1, is formed with a longitudinal curvature. As inmy copending application, the tunnel 15 has a progressively diminishingtransverse width in its forward portion. The planing surfaces 17 eachextend rearwardly from their juncture with one of the bow stems 16 tothe stern 14 and are slightly inclined transversely outwardly andupwardly-from their juncture 18 with the adjacent outer sides of thetunnel 15.

' The outer'edges of the planing surfaces 17 adjoin out- "ice wardly andupwardly inclined non-trip surfaces 19. The latter extend from the stern14 to points adjacent the bow end 13 and each adjoins the lower edge ofone of the side walls 12 and the associated stem 16. The non-tripsurfaces 19 contiguous to their junctures 20 with the associated sidewalls 12 are each formed with a portion 21 which extends outwardly andslightly downwardly from the main portion of the associated surface 19.The portions 21 serve to direct displaced water outwardly and downwardlyand thereby act as spray deflecting surfaces.

Referring to FIGURES 1 and 2, it will be seen that the planing surfaces17 form junctures 18 with the upright side walls 22 of the tunnel 15.Said walls 22 extend along the transversely flat rear portion 23 to theoutwardly curved fore portion of the tunnel 15. There the walls 22 areterminated by transversely extending walls 22', but the sides of thetunnel 15 downwardly therefrom and are longitudinally curved outwardlyas at 17, thereby to allow water and air to readily flow over the curvedportion, the walls 22' and the surfaces 23 and thus preventing blockingthe flow of water and air thru the tunnel 15 at high speeds.

As shown in FIGURES 3 and 4 the upright side walls 22 of the rear halfof the tunnel 15 extend downwardly from the flat portions 23 thereof,preferably at an angle of the order of to join the planing surfaces 17at the junctures 18. Midway between the planing surfaces 17, the tunnel15 is formed with a wedge-shaped, combined displaced water dividing andplaning member 24 which, as best seen in FIGURE 2, extends forwardlyfrom the stern 14 to a point slightly forwardly of the transverse planeof the junctures of the stems 16 with the planing surfaces 17.

The member 24 is formed for the major portion of its length with asubstantially blunted wedge cross section and extends longitudinally ofthe hull midway between the sides of the tunnel 15. The sides 25 of themember 24 are each inclined upwardly and outwardly from the outer edgesof the relatively inclined bottom portions 26, and preferably meet inthe flat roof portion 23 of the tunnel 15 at an angle of the order of 45As the member 24 extends forwardly the angles of the relatively inclinedbottom portions 26 are progressively diminished, as shown by FIGURES 4and 5, so that adjacent its forward end the bottom er the member 24 isnarrower and has a relatively sharp V-shape in cross section. Thus thecross-sectional open area of the tunnel 15 is further increased at itsforward end and the flow of water into the tunnel is fa cilitated.At'the stem end of the member 24 the sides 25 are flared laterallyslightly as'shown at 27, thus restricting to a certain extent flowthrough the tunnel 15 at the stern and guiding the water passing fromthe tunnel away from the stern end of the member 24 and the propeller ofan outboard motor which may be mounted on the hull transom with thepropeller aft of the member 24, there by minimizing cavitation.

As clearly shown in FIGURES 1-3 the bottom por tions 26 of the member 24are forwardly and upwardly inclined from a plane approximatelyone inch(1") below the plane of the stern ends of the planing surfaces 17.

'(FIGURE 3) to a plane approximately one inch (1").

hull from a selected straight course or a curved turn path. Since eachof the surfaces 17 is an outwardly and upwardly inclined plane and thenon-trip surfaces 19 extend outwardly and upwardly therefrom it will beapparent that due to the inclined relation of the surfaces 17 and 19 tothe member 24 each side of the stern end of the hull is provided withwhat is known as a dead rise. This permits the bull to be readily tiltedabout the member 24 as a fulcrum toward the inner side of a selectedturn path without causing undue outward swinging movement of the sternend of tle hull from said path, and without causing the tripping oroverturning tendency found in prior hulls not provided with the featuresof my present invention.

Thus formed and arranged, the wedge-shaped member 24 also serves todivide and direct water and air displaced into the tunnel by the bowstems 16 into separate, laterally spaced portions of the tunnel so thatsuch displaced water, which is more or less deturbulated by the actionof the tunnel portions 22, 22 and 23 and the member 24, is directedoutwardly away from the path of the propeller of the motor which may besecured to the stern 14 in the usual manner. It will be obvious to thoseskilled in the art that by directing such water away from the path ofthe propeller said propeller will rotate with less cavitation and willtherefore operate more efficiently.

Assuming that the hull is making a tight left hand turn and is tiltedtoward the inner left side of said turn, so that the mean water level isapproximately that indicated by the broken line L in FIGURE 3, it willbe seen that the inclinations of the outer or right hand non-tripsurface 19 and the associated planing surface 17 will cooperatively actin lifting the then outer side of the hull to maintain the inclinationof the hull. It will also be seen that the associated surfaces 22, 23and at each side of the member 24 resist outward swinging of the sternend of the hull and allow it to closely follow the left selected turnpath.

In other words, during a turn of the hull to the left, the upright lefthand surface 22 of the tunnel 15 tends to force displaced water againstits left hand surfaces 23, 25 and 26, and the right hand surfaces 25 and26 force such water against the right hand upright surface 22, wherebysaid surfaces tend to maintain the stem end of the hull against outwardswinging movement to the right from the selected left turn path.

It will be obvious that during a turn of the hull to the rightcorresponding but opposed action takes place whereby outward swinging ofthe stern end of the bull to the left of a selected turn path isresisted.

The shape, size, form, relation and proportion of the bottom surfaces ofthe hull to one another, especially those of the tunnel 15, the member24, the planning surfaces 17, the non-trip surfaces 19, the uprightsurfaces 22, the flat surfaces 23 and the inclined surfaces 25 and 26 ofthe member 24 must closely approximate those shown and described, forthe reasons that extensive experimentation reveals that even minorchanges in the shape, relation, etc. of said bottom surfaces mayadversely affect the desired result.

In order to attain a maximum top speed from a given amount of propulsiveforce my present hull, as in my prior hull, may have each of its planingsurfaces 17 divided intermediate its ends by a downwardly offset portionproviding a step between its front portion 28 and its rear portion 29 sothat when the hull reaches a planing speed and altitude it planes on theportions 28 and 29 and as the speed increases, rides on decreasing rearportions of said portions, thereby reducing their wetted area andallowing, as described below, escape of air thru said steps.

As shown in FIGURE 4, between the front portions 28 of the planingsurfaces 17 and the rear portions 29 of said surfaces there are providedintermediate step spaces 30 for the escape of air from the tunnel 15.The spaces 30 extend outwardly across and slightly below the planes ofthe surfaces 29 and below the junctures 18 and are each in communicationwith an inwardly projecting step 31 formed in the contiguous non-tripsurface 19 and in a step 32 formed inwardly in the contiguous side wall12. The spaces 30, 31 and 32 are contiguously extended from. the tunnel15 and are extended above the normal water level of the sides 12 of thehull to atmosphere, whereby a flow of air through the tunnel induces apredetermined flow of air through the spaces30, 31 and 32 to atmosphereand thereby prevent the blocking of air across and through the spaces30, 31 and 32.

A bull constructed in accordance with the principles illustrated anddescribed above fully meets the objects of my present invention,however, it should be understood that the herein disclosed form of saidinvention is intended to exemplify its principles and that variousmodifications and rearrangements of its component surfaces may be madewithin the scope of the appended claims wherein I claim:

1. A speed boat hull of the planing type wherein the hull bottom isprovided with a pair of how stems spaced inwardly from the sides of saidhull and spaced laterally from each other and each of said bow stemshas, adjoining and extending rearwardly therefrom, a planing surfacewhich has a substantially flat portion, which comprises: an elongatedwall extending upwardly from the inner edge of each of said planingsurfaces, a central, longitudinally extending tunnel defined by saidwalls and the associated bow stems, and having as a roof the bottom ofsaid hull, a tunnel-dividing and planing member projecting downwardlyfrom the roof of said tunnel and extending longitudinally and centrallyof said tunnel from the stern of said hull to a forward point adjacentthe area wherein said how stems adjoin said planing surfaces, saidmember having sides that are inclined with respect to the roof of saidtunnel and to the bottom of said member, said sides and said bottom ofsaid member, at the forward end of said member, terminating insubstantial- 1y a point, and said bottom of said member being forwardlyand upwardly inclined from a plane surface at the stern of said hulllying below the lowest point of said planing surfaces, and said tunnelbeing free from projections thereinto other than said member and beingsubstantially uniform in width from the stern forwardly for more thanhalf its length.

2. A speed boat hull as set forth in claim 1 in which the side walls ofsaid tunnel are substantially vertical.

3. A speed boat hull as set forth in claim 1 in which said planingsurfaces are outwardly and upwardly inclined.

4. A speed boat hull as set forth in claim 1 in which, adjacent thestern end of said member, the sides only of said member are flaredslightly outwardly thereby narrowing the portion of said tunnel on eachside of said member.

5. A speed boat hull as set forth in claim 1 in which the roof of saidtunnel is substantially fiat.

6. A speed boat hull as set forth in claim 2 in which said planingsurfaces are outwardly and upwardly inclined.

7. A speed boat hull as set forth in claim 2 in which, adjacent thestern end of said member, the sides only of said member are flaredslightly outwardly thereby narrowing the portion of said tunnel on eachside of said member.

8. A speed boat hull as set forth in claim 2 in which the roof of saidtunnel is substantially flat.

9. A speed boat hull as set forth in claim 5 in which, adjacent thestern end of said member, the sides'only of said member are flaredslightly outwardly thereby narrowing the portion of said tunnel on eachside of said mem' ber.

10. A speed boat hull as set forth in claim 6 in which. adjacent thestern end of said member, the sides only of 2,020,792 Maynard Nov. 12,1935 6 Martin May 31, 1960 Mills Aug. 8, 1961 Canazzi Aug. 28, 1962FOREIGN PATENTS Great Britain "of 1881

1. A SPEED BOAT HULL OF THE PLANING TYPE WHEREIN THE HULL BOTTOM ISPROVIDED WITH A PAIR OF BOW STEMS SPACED INWARDLY FROM THE SIDES OF SAIDHULL AND SPACED LATERALLY FROM EACH OTHER AND EACH OF SAID BOW STEMSHAS, ADJOINING AND EXTENDING REARWARDLY THEREFROM, A PLANING SURFACEWHICH HAS A SUBSTANTIALLY FLAT PORTION, WHICH COMPRISES: AN ELONGATEDWALL EXTENDING UPWARDLY FROM THE INNER EDGE OF EACH OF SAID PLANINGSURFACES, A CENTRAL, LONGITUDINALLY EXTENDING TUNNEL DEFINED BY SAIDWALLS AND THE ASSOCIATED BOW STEMS, AND HAVING AS A ROOF THE BOTTOM OFSAID HULL, A TUNNEL-DIVIDING AND PLANING MEMBER PROJECTING DOWNWARDLYFROM THE ROOF OF SAID TUNNEL AND EXTENDING LONGITUDINALLY AND CENTRALLYOF SAID TUNNEL FROM THE STERN OF SAID HULL TO A FORWARD POINT ADJACENTTHE AREA WHEREIN SAID BOW STEMS ADJOIN SAID PLANING SURFACES, SAIDMEMBER HAVING SIDES THAT ARE INCLINED WITH RESPECT TO THE ROOF OF SAIDTUNNEL AND TO THE BOTTOM OF SAID MEMBER, SAID SIDES AND SAID BOTTOM OFSAID MEMBER, AT THE FORWARD END OF SAID MEMBER, TERMINATING INSUBSTANTIALLY A POINT, AND SAID BOTTOM OF SAID MEMBER BEING FORWARDLYAND UPWARDLY INCLINED FROM A PLANE SURFACE AT THE STERN OF SAID HULLLYING BELOW THE LOWEST POINT OF SAID PLANING SURFACES, AND SAID TUNNELBEING FREE FROM PROJECTIONS THEREINTO OTHER THAN SAID MEMBER AND BEINGSUBSTANTIALLY UNIFORM IN WIDTH FROM THE STERN FORWARDLY FOR MORE THANHALF ITS LENGTH.